Further studies are proposed on the mechanisms of the reactions catalyzed by and on the structure-function relationships involved in the regulation of glutamine synthetase, glutamine-dependent carbamyl phosphate synthetase, aspartate beta-decarboxylase, glutamine transaminase, and closely related enzymes. BIBLIOGRAPHIC REFERENCES: Meister, A.: Function of the gamma-Glutamyl Cycle in Amino Acid Transport, Proceedings of the International Symposium on Amino Acid Transport and Uric Acid Transport, Innsbruck, Austria, June 15-17, 1975 pp. 40-46; (editors: Silbernagl, S., Lang, F. and Greger, R.); publisher, Geort Thieme, 1976. Sekura, R., Hochreiter, M., and Meister, A.: alpha-Aminomethylglutarate, alpha Beta-Amino Acid Analog of Glutamate that Interacts with Glutamine Synthetase and the Enzymes that Catalyze Glutathione Synthesis, Journal of Biological Chemistry, 251, 2263-2270, 1976.